Makefile for C code - c

Question

I inherited a code which has a makefile, but so far I was unable to run it on a linux server. The main complain of the compiler is that it is unable to load libgmp.so.3 : error while loading shared libraries: libgmp.so.3. I know that libgmp.so.10 exists on this server, but I was wondering which part of the makefile needs to be changed so the compiler looks for libgmp.so.10 rather than libgmp.so.3.
OPTFLAG = -O2 -Wall -fPIC -fexceptions -DNDEBUG
LDFLAGS = -O2 -Wl,-no_compact_unwind -DNDEBUG -lm -pthread
COMPILER = gcc ${OPTFLAG}
LINKER = gcc ${LDFLAGS}
# CPLEX directory
CPLEX_HOME = /opt/ibm/ILOG/CPLEX_Studio1263/cplex
CPLEX_INC = ${CPLEX_HOME}/include/
CPLEX_LIB = ${CPLEX_HOME}/lib/x86-64_linux/static_pic/ -lcplex
# Compile the main file
code: code.c
${COMPILER} -c code.c -o code.o -I${CPLEX_INC}
${LINKER} -o code code.o -L${CPLEX_LIB}
clean::
rm -f *.o
rm -f ${LIB}/*.o
rm -f *~
rm -f ${SRC}/*~ ${INCLUDE}/*~

Answer 1

You need to rebuild whatever program or library uses libgmp.so.3 from source code. Could you provide the exact command run by make and the error message it produces?
EDIT The problem here is that the system has installed a version of the IBM CPLEX software which comes with its own GCC binary, and that GCC binary uses libgmp.so.3. The easiest way to fix this would be to upgrade the CPLEX software to a version which supports the operating system being used, or use the software on the operating system for which it was written (i.e., something really old that actually ships libgmp.so.3).

Answer 2

The most easy way it to install libgmp-dev package, from your linux distribution. GMP is a package library to do multiple precision calculations on large integers, which is probably needed by your program. As you put in some comments, adding -L/usr/lib64/libgmp.so.10 is an error, as -L option allows to add a directory to search for libraries, and not a specific library.
If only the library is needed and no header file is missing in your compilation (this is something strange, but sometimes happen) then you can still link with only the libgmp.so.10 object, but you have to do in a something nasty way. Just add /usr/lib64/libgmp.so.10 as an object file (not a library, with -l option) to your link command.
EDIT
From looking more closely your Makefile I see no reference to the libgmp.so.3 library, so I only can assume this is a indirect reference from some other already compiled library that comes from outside with your package. Just use
ldd lib<nameOfLibrary>.so.x.x
with all the libraries needed by your final executable, so see which shared objetc is the one that requests libgmp.so.3 soname, and then recompile it, reinstall it, or use your system's libraries ONLY, and not mesh anymore with libraries coming from another system. For example you can try (this is an expensive command, but it will get the answer)
find / -name "lib*.so.*" -print | xargs ldd > all_libs.lddout
and then find all_libs.lddout to see which library uses libgmp.so.3 (this will be the outdated library) You'll need to deinstall it or upgrade it, to be able to continue.
Linux systems have a library version system that allows an executable to be able to load different versions of the same library and allow them to live together in the same system. One of two: or you are able to locate the sources of version 3 of the shared libgmp.so.3 library and install it on your system, or you'll need to update the libraries your program uses to be able to link with the libgmp.so.10 already installed on your system.
2ND EDIT
As I see in the comments, you have changed the default compiler on your system by another coming possibly from other linux distribution (as your installed library is libgmp.so.10 while the one cc1 requests is libgmp.so.3, which is not installed on your system.
Installing a different compiler from the one you have installed, and doing that without previously deinstalling the other compiler, can lead you to this kind of problems.
The most reliable thing you can do is to reinstall the compiler from your distribution, or better, reinstall the whole linux system, as you have probably broken many things that will be emerging as you use your system. There's very poor info on what you have done to go further in your problem. Anyway, my recommendation is to not use the comment parts to add new information about your problem, just edit your question and add all those new information to it.